Audi's S7 Sportback is one slick luxury ride, and now the specialists at ABT have made it even more so with its latest tuning package. Dubbed the AS7, the German tuning house has given the top-of-the-line Sportback more power and better handling. Output from the 4.0-liter twin-turbo V8, for starters, has increased by 100 hp and 74 lb-ft of torque resulting in a total of 520 hp and 479 lb-ft of torque.